维生素K3粉末降解动力学

在温度为50～90℃,相对湿度为50～93%范围内,维生素K₃的变色速率方程为—dR/dt=k_RR,降解速率方程为d(C_o—c)/dt=k_C(c_o—c)^1/2,光解速率方程为—dR/dt=k_P(R_o—R)^-1。k_R和_C与热力学温度T和相对湿度RH的关系通式为k=k′exp(—E_A/RT)exp(m′RH)。在实验温度和湿度范围内,变色和降解的表观活化能平均值分别为105.51和130.72 kJ/mol。     

An open-label study of lamotrigine adjunct or monotherapy for the treatment of adolescents with bipolar depression

OBJECTIVE: The treatment of pediatric bipolar depression has not been well studied. The authors wished to prospectively study the efficacy of lamotrigine as adjunctive or monotherapy in adolescents with bipolar disorder who were experiencing a depressive episode. METHOD: This was an 8-week open-label trial of lamotrigine with 20 adolescents ages 12-17 years (mean age 15.8; 7 boys, 13 girls) with diagnoses of bipolar disorder I, II, or not otherwise specified, who were experiencing a depressive episode. Lamotrigine was begun at 12.5 to 25 mg/day. Primary response criteria was a 1 or a 2 on the Clinical Global Impression-Improvement at week 8. A secondary criterion was at least a 50% decrease in Children's Depression Rating Scale-Revised scores. RESULTS: Nineteen subjects completed the trial. The mean final dose was 131.6 mg/day. Seven subjects were taking other psychotropic medications. Sixteen subjects (84%) responded by primary criteria, and 12 (63%) responded to our secondary criteria. Eleven subjects (58%) were considered in remission at week 8. Young Mania Rating Scale and Overt Aggression Scale-Modified scores also decreased significantly during the trial. There was no significant weight change, rash, or other adverse effects during the trial. CONCLUSIONS: Adolescents with bipolar depression appeared to respond to lamotrigine treatment, whether as adjunctive therapy or monotherapy, with decreases in depression, mania, and aggression. Larger, placebo-controlled studies of lamotrigine are needed in this population.     

Mandatory Procedures and Fairness in Mental Impairment Hearings

Uncertainty has attended procedures for adjudging unfitness to stand trial in Victoria pursuant to the Crimes (Mental Impairment and Unfitness to be Tried) Act 1997 (Vic) and how “special hearings” should be conducted when a person is determined to be unfit to stand trial but does not wish to pursue the defence of not guilty because of mental impairment. In R v Langley [2008] VSCA 81, (2009) 19 VR 90 the Victorian Court of Appeal clarified the procedures to be employed at jury trials on such matters and quashed a decision not in conformity with proper procedures, making clear that denial of fairness to such accused persons has the potential to result in appealable error.     

Human Rights and Review of the Involuntary Status of Patients with a Mental Illness: Kracke after Momcilovic

Arguably, Australia's most significant judicial pronouncement on the human rights of those with mental illnesses was made in 2009 by Justice Bell, the then President of the Victorian Civil and Administrative Tribunal (“VCAT”). The decision is an exhaustive analysis of the application of the Charter of Human Rights and Responsibilities Act 2006 (Vic) to the involuntary status of a person subject to a community treatment order in Victoria. It occurred in the context of delays in the conduct of reviews of the status of a mentally ill person by Victoria's Mental Health Review Board (“the Board”). The outcome of the hearing was a declaration that the Board had breached the person's human rights to a fair hearing, even though the person's involuntary status on a community treatment order was not disturbed by VCAT. Whilst some important aspects of Justice Bell's decision concerning the general methodology to be applied when analysing human rights were overturned in the subsequent Court of Appeal decision of R v Momcilovic [2010] VSCA 50, the latter decision did not concern mental health and so leaves Kracke as the most detailed articulation and analysis of human rights within this difficult sphere.     

Rhombomere-specific analysis reveals the repertoire of genetic cues expressed across the developing hindbrain

Background

Maintaining the correct balance of proliferation versus differentiation in retinal progenitor cells (RPCs) is essential for proper development of the retina. The cell cycle regulator cyclin D1 is expressed in RPCs, and mice with a targeted null allele at the cyclin D1 locus (Ccnd1 ^-/-) have microphthalmia and hypocellular retinas, the latter phenotype attributed to reduced RPC proliferation and increased photoreceptor cell death during the postnatal period. How cyclin D1 influences RPC behavior, especially during the embryonic period, is unclear.

Results

In this study, we show that embryonic RPCs lacking cyclin D1 progress through the cell cycle at a slower rate and exit the cell cycle at a faster rate. Consistent with enhanced cell cycle exit, the relative proportions of cell types born in the embryonic period, such as retinal ganglion cells and photoreceptor cells, are increased. Unexpectedly, cyclin D1 deficiency decreases the proportions of other early born retinal neurons, namely horizontal cells and specific amacrine cell types. We also found that the laminar positioning of horizontal cells and other cell types is altered in the absence of cyclin D1. Genetically replacing cyclin D1 with cyclin D2 is not efficient at correcting the phenotypes due to the cyclin D1 deficiency, which suggests the D-cyclins are not fully redundant. Replacement with cyclin E or inactivation of cyclin-dependent kinase inhibitor p27Kip1 restores the balance of RPCs and retinal cell types to more normal distributions, which suggests that regulation of the retinoblastoma pathway is an important function for cyclin D1 during embryonic retinal development.

Conclusion

Our findings show that cyclin D1 has important roles in RPC cell cycle regulation and retinal histogenesis. The reduction in the RPC population due to a longer cell cycle time and to an enhanced rate of cell cycle exit are likely to be the primary factors driving retinal hypocellularity and altered output of precursor populations in the embryonic Ccnd1 ^-/- retina.     

Is improvement in impaired cognition and depressive symptoms in post‐stroke patients associated with recovery in activities of daily living?

Background and purpose – Depression and cognitive impairment after stroke are associated with physical functional outcomes, but there are limited data on whether depressive symptoms and cognitive status and improvements independently influence functional status and recovery. Methods – In a 6‐month prospective cohort study of 141 post‐acute stroke patients, demographic and clinical data on admission, and neurological, cognitive, depressive symptoms and functional variables on admission and at 6 months after stroke were measured using the National Institute of Health Stroke Scale (NIHSS), Abbreviated Mental Test (AMT), Geriatric Depression Scale (GDS) and Barthel Index (BI). Results – On multivariate analysis, severe activities of daily living (ADL) dependence at 6 months was significantly less likely associated with higher baseline AMT score denoting better cognitive status (OR = 0.68, 95% CI 0.48–0.97 per score point) and with greater AMT change score denoting greater cognitive improvement (OR = 0.61, 95% CI 0.41–0.91 per change score point); it was also more likely with higher baseline NIHSS scores denoting severe neurological impairment, (OR = 1.74, 95% CI 1.13–2.63 per point score), NIHSS change score [denoting lesser neurological improvement (OR = 1.83, 95% CI 1.13–2.93 per unit change score)], but was not associated with baseline or change scores of GDS. Greater magnitudes of functional recovery [BI change score (standardized beta)] were associated with better baseline depressive symptoms (?0.21) and improvement (?0.31), but not with cognitive status or improvement, in the presence of other significant variables, neurological status (?0.89) and improvement (?0.65), lower baseline physical functional status (?0.85) and younger age (?0.23). Conclusions – These data suggest that improving depressive symptoms in stroke patients may accelerate functional recovery, but the level of physical functioning achieved post‐stroke is determined by neurological and cognitive factors, consistent with the evidence that improvement of depressive symptoms through therapeutic intervention is limited by cognitive impairment.     

Patulin causes DNA damage leading to cell cycle arrest and apoptosis through modulation of Bax, p and p proteins in skin of mice

Patulin (PAT), a mycotoxin found in apples, grapes, oranges, pear and peaches, is a potent genotoxic compound. WHO has highlighted the need for the study of cutaneous toxicity of PAT as manual labour is employed during pre and post harvest stages, thereby causing direct exposure to skin. In the present study cutaneous toxicity of PAT was evaluated following topical application to Swiss Albino mice. Dermal exposure of PAT, to mice for 4 h resulted in a dose (40-160 μg/animal) and time (up to 6 h) dependent enhancement of ornithine decarboxylase (ODC), a marker enzyme of cell proliferation. The ODC activity was found to be normal after 12 and 24 h treatment of patulin. Topical application of PAT (160 μg/100 μl acetone) for 24-72 h caused (a) DNA damage in skin cells showing significant increase (34-63%) in olive tail moment, a parameter of Comet assay (b) significant G 1 and S-phase arrest along with induction of apoptosis (2.8-10 folds) as shown by annexin V and PI staining assay through flow cytometer. Moreover PAT leads to over expression of p^21/WAF1 (3.6-3.9 fold), pro apoptotic protein Bax (1.3-2.6) and tumor suppressor wild type p⁵³ (2.8-3.9 fold) protein. It was also shown that PAT induced apoptosis was mediated through mitochondrial intrinsic pathway as revealed through the release of cytochrome C protein in cytosol leading to enhancement of caspase-3 activity in skin cells of mice. These results suggest that PAT has a potential to induce DNA damage leading to p⁵³ mediated cell cycle arrest along with intrinsic pathway mediated apoptosis that may also be correlated with enhanced polyamine production as evident by induction of ODC activity, which may have dermal toxicological implications.     

N-(3-acetylaminophenyl)piperazine hydrochloride (BEA 1654), a putative 5-HT1 agonist, causes constriction of arteriovenous anastomoses and dilatation of arterioles

Using 3H-ligands and radioactive microspheres we studied the binding characteristics and the effects on the distribution of carotid arterial blood flow of n-(3-acetylaminophenyl)piperazine hydrochloride (BEA 1654). The compound had a Ki value of 32 nM (5-HT: 8 nM) on 5-HT1 but no or very weak affinity for 5-HT2, alpha 1- and alpha 2-adrenoceptor sites in rat cerebral cortex homogenates. Intracarotid infusions of BEA 1654 (0.1-1.0 mg X kg-1 X min-1) were nearly equieffective in untreated and treated (phentolamine plus ketanserin) pigs in redistributing carotid arterial blood towards the nutrient compartment (particularly the skin and ears) at the expense of shunting via arteriovenous anastomoses (AVAs). In view of the high and selective affinity of BEA 1654 to 5-HT1 binding sites, the similarity of pharmacological responses between 5-HT and BEA 1654, and the ineffectiveness of antagonists of 5-HT2 and alpha-adrenergic receptors to block the AVA constriction and arteriolar dilatation caused by both 5-HT and BEA 1654, we conclude that these effects are mediated by 5-HT1 receptors. The vast difference between the ratios of Ki values for 5-HT1 binding sites and of the pharmacologically effective doses of BEA 1654 and 5-HT suggests that either BEA 1654 may be a partial agonist of 5-HT1 receptors or, while the drug binds with both subsets of 5-HT1 receptors, it is only one type which mediates the pharmacological response.